A stuck vent valve scuttled the test, a crucial test before its launch, scheduled for no earlier than June.
The second time was not the charm. NASA has had to suspend the wet general test of its lunar mega-rocket, with which it plans to take the first woman and the first person of color to the Moon in 2025. It is a key test to set a date definitive to the Artemis I mission, the first of the program that, although it will not be manned, will kick off the continued human presence on our satellite since this decade.
A stuck vent valve atop the mobile launcher structure that supports Artemis 1’s SLS (Space Launch System) mega-rocket forced NASA to suspend the test after fueling began, as confirmed by the US space agency to Space.com. The valve is used to relieve pressure from the core stage of the rocket during fueling.
“Due to the vent valve issue, the launch director has canceled test for the day,” Jeremy Parsons, NASA deputy director for ground systems, wrote in a Twitter update after the suspension. “The team is preparing to offload LOX (liquid oxygen) and will begin discussing when the vehicle can be prepared for the next attempt.” That is, NASA will seek a new date to repeat the test.
The vent valve was at the 49-meter level (160 from the mobile launcher), which serves as the gantry and launch pad for the SLS, according to Parsons. NASA officials said the problem occurred in a panel that controls the valve, leaving technicians unable to open it.
“Given time to resolve the issue, as teams neared the end of their shifts, the launch director made the call to halt testing for the day,” NASA wrote in a statement Monday, April 4. “A team will investigate the issue on the platform, and the team will review range availability and the time needed to change systems before making a determination on the way forward.”
Monday’s refueling attempt was NASA’s second attempt to fill the SLS rocket’s core stage with 2.6 million liters of supercooled liquid oxygen and liquid hydrogen in a dress rehearsal the agency calls a “wet dress rehearsal.” (or ‘wet dress rehearsal’). The test, which began on April 1, consists of a complete launch countdown rehearsal, including the refueling process, until just ten seconds before the launch order.
NASA attempted to refuel the Artemis 1 moon rocket on Sunday, April 3 but was stopped before propellant loading began due to a problem with pressurization in the mobile launcher that keeps dangerous gases out of the enclosed areas where technicians work. By Monday, technicians had loaded about 50% of the liquid oxygen needed for the fuel test before the suspension, Parsons wrote on Twitter.
The launch of Artemis I, without a specific date, is considered not before next June, but the setbacks in this crucial test could delay its launch.
